patch-2.4.4 linux/arch/mips/mips-boards/atlas/atlas_int.c

• Lines: 249
• Date: Fri Apr 13 20:26:07 2001
• Orig file: v2.4.3/linux/arch/mips/mips-boards/atlas/atlas_int.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.3/linux/arch/mips/mips-boards/atlas/atlas_int.c linux/arch/mips/mips-boards/atlas/atlas_int.c
@@ -0,0 +1,248 @@
+/*
+ * Carsten Langgaard, carstenl@mips.com
+ * Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
+ *
+ * ########################################################################
+ *
+ *  This program is free software; you can distribute it and/or modify it
+ *  under the terms of the GNU General Public License (Version 2) as
+ *  published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope it will be useful, but WITHOUT
+ *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ *  for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * ########################################################################
+ *
+ * Routines for generic manipulation of the interrupts found on the MIPS 
+ * Atlas board.
+ *
+ */
+#include <linux/config.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+
+#include <asm/irq.h>
+#include <asm/mips-boards/atlas.h>
+#include <asm/mips-boards/atlasint.h>
+#include <asm/gdb-stub.h>
+
+
+struct atlas_ictrl_regs *atlas_hw0_icregs
+	= (struct atlas_ictrl_regs *)ATLAS_ICTRL_REGS_BASE;
+
+extern asmlinkage void mipsIRQ(void);
+extern void do_IRQ(int irq, struct pt_regs *regs);
+
+unsigned long spurious_count = 0;
+irq_desc_t irq_desc[NR_IRQS];
+
+#if 0
+#define DEBUG_INT(x...) printk(x)
+#else
+#define DEBUG_INT(x...)
+#endif
+
+void disable_atlas_irq(unsigned int irq_nr)
+{
+	atlas_hw0_icregs->intrsten = (1 << irq_nr);
+}
+
+void enable_atlas_irq(unsigned int irq_nr)
+{
+	atlas_hw0_icregs->intseten = (1 << irq_nr);
+}
+
+static unsigned int startup_atlas_irq(unsigned int irq)
+{
+	enable_atlas_irq(irq);
+	return 0; /* never anything pending */
+}
+
+#define shutdown_atlas_irq	disable_atlas_irq
+
+#define mask_and_ack_atlas_irq disable_atlas_irq
+
+static void end_atlas_irq(unsigned int irq)
+{
+	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+		enable_atlas_irq(irq);
+}
+
+static struct hw_interrupt_type atlas_irq_type = {
+	"Atlas",
+	startup_atlas_irq,
+	shutdown_atlas_irq,
+	enable_atlas_irq,
+	disable_atlas_irq,
+	mask_and_ack_atlas_irq,
+	end_atlas_irq,
+	NULL
+};
+
+int get_irq_list(char *buf)
+{
+	int i, len = 0;
+	int num = 0;
+	struct irqaction *action;
+
+	for (i = 0; i < ATLASINT_END; i++, num++) {
+		action = irq_desc[i].action;
+		if (!action) 
+			continue;
+		len += sprintf(buf+len, "%2d: %8d %c %s",
+			num, kstat.irqs[0][num],
+			(action->flags & SA_INTERRUPT) ? '+' : ' ',
+			action->name);
+		for (action=action->next; action; action = action->next) {
+			len += sprintf(buf+len, ",%s %s",
+				(action->flags & SA_INTERRUPT) ? " +" : "",
+				action->name);
+		}
+		len += sprintf(buf+len, " [hw0]\n");
+	}
+	return len;
+}
+
+int request_irq(unsigned int irq, 
+		void (*handler)(int, void *, struct pt_regs *),
+		unsigned long irqflags, 
+		const char * devname,
+		void *dev_id)
+{  
+        struct irqaction *action;
+
+	DEBUG_INT("request_irq: irq=%d, devname = %s\n", irq, devname);
+
+	if (irq >= ATLASINT_END)
+		return -EINVAL;
+	if (!handler)
+		return -EINVAL;
+
+	action = (struct irqaction *)kmalloc(sizeof(struct irqaction), GFP_KERNEL);
+	if(!action)
+		return -ENOMEM;
+
+	action->handler = handler;
+	action->flags = irqflags;
+	action->mask = 0;
+	action->name = devname;
+	action->dev_id = dev_id;
+	action->next = 0;
+	irq_desc[irq].action = action;
+	enable_atlas_irq(irq);
+
+	return 0;
+}
+
+void free_irq(unsigned int irq, void *dev_id)
+{
+	struct irqaction *action;
+
+	if (irq >= ATLASINT_END) {
+		printk("Trying to free IRQ%d\n",irq);
+		return;
+	}
+
+	action = irq_desc[irq].action;
+	irq_desc[irq].action = NULL;
+	disable_atlas_irq(irq);
+	kfree(action);
+}
+
+static inline int ls1bit32(unsigned int x)
+{
+	int b = 31, s;
+
+	s = 16; if (x << 16 == 0) s = 0; b -= s; x <<= s;
+	s =  8; if (x <<  8 == 0) s = 0; b -= s; x <<= s;
+	s =  4; if (x <<  4 == 0) s = 0; b -= s; x <<= s;
+	s =  2; if (x <<  2 == 0) s = 0; b -= s; x <<= s;
+	s =  1; if (x <<  1 == 0) s = 0; b -= s;
+
+	return b;
+}
+
+void atlas_hw0_irqdispatch(struct pt_regs *regs)
+{
+	struct irqaction *action;
+	unsigned long int_status;
+	int irq, cpu = smp_processor_id();
+
+	int_status = atlas_hw0_icregs->intstatus; 
+
+	/* if int_status == 0, then the interrupt has already been cleared */
+	if (int_status == 0)
+		return;
+
+	irq = ls1bit32(int_status);
+	action = irq_desc[irq].action;
+
+	DEBUG_INT("atlas_hw0_irqdispatch: irq=%d\n", irq);
+
+	/* if action == NULL, then we don't have a handler for the irq */
+	if ( action == NULL ) {
+		printk("No handler for hw0 irq: %i\n", irq);
+		spurious_count++;
+		return;
+	}
+
+	irq_enter(cpu, irq);
+	kstat.irqs[0][irq]++;
+	action->handler(irq, action->dev_id, regs);
+	irq_exit(cpu, irq);
+
+	return;		
+}
+
+unsigned long probe_irq_on (void)
+{
+	return 0;
+}
+
+
+int probe_irq_off (unsigned long irqs)
+{
+	return 0;
+}
+
+#ifdef CONFIG_REMOTE_DEBUG
+extern void breakpoint(void);
+extern int remote_debug;
+#endif
+
+void __init init_IRQ(void)
+{
+	int i;
+
+	/* 
+	 * Mask out all interrupt by writing "1" to all bit position in 
+	 * the interrupt reset reg. 
+	 */
+	atlas_hw0_icregs->intrsten = 0xffffffff;    
+
+	/* Now safe to set the exception vector. */
+	set_except_vector(0, mipsIRQ);
+
+	for (i = 0; i <= ATLASINT_END; i++) {
+		irq_desc[i].status	= IRQ_DISABLED;
+		irq_desc[i].action	= 0;
+		irq_desc[i].depth	= 1;
+		irq_desc[i].handler	= &atlas_irq_type;
+	}
+
+#ifdef CONFIG_REMOTE_DEBUG
+	if (remote_debug) {
+		set_debug_traps();
+		breakpoint();
+	}
+#endif
+}